Shallow DOF

On 11/6/2016 12:03 AM, RichA wrote:
http://www.pbase.com/andersonrm/imag...71533/original


Did you use a close up attachment?


--
PeterN

In article ,
RichA wrote:

On Sunday, 6 November 2016 13:36:21 UTC-5, peterN wrote:
On 11/6/2016 12:03 AM, RichA wrote:
http://www.pbase.com/andersonrm/imag...71533/original


Did you use a close up attachment?


--
PeterN

No, "macro" mode on a cheap zoom.

Exif:

Lens ID: Sigma DL Zoom 75-300mm F4-5.6 or Sigma 70-300mm F4-5.6 M

That lense seems to have a following. Are you happy with it?

http://www.pentaxforums.com/userrevi...5-6-dl-macro.h
tml
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teleportation kills

On 11/6/2016 2:29 PM, RichA wrote:
On Sunday, 6 November 2016 13:36:21 UTC-5, peterN wrote:
On 11/6/2016 12:03 AM, RichA wrote:
http://www.pbase.com/andersonrm/imag...71533/original


Did you use a close up attachment?


--
PeterN

No, "macro" mode on a cheap zoom.


That's why your DOF is so shallow.

--
PeterN

In article ,
PeterN wrote:

On 11/6/2016 2:29 PM, RichA wrote:
On Sunday, 6 November 2016 13:36:21 UTC-5, peterN wrote:
On 11/6/2016 12:03 AM, RichA wrote:
http://www.pbase.com/andersonrm/imag...71533/original


Did you use a close up attachment?


--
PeterN

No, "macro" mode on a cheap zoom.


That's why your DOF is so shallow.

Because of the cheepo plastic? :-))
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teleportation kills

In article ,
RichA wrote:

On Sunday, 6 November 2016 16:12:58 UTC-5, android wrote:
In article ,
PeterN wrote:

On 11/6/2016 2:29 PM, RichA wrote:
On Sunday, 6 November 2016 13:36:21 UTC-5, peterN wrote:
On 11/6/2016 12:03 AM, RichA wrote:
http://www.pbase.com/andersonrm/imag...71533/original


Did you use a close up attachment?


--
PeterN

No, "macro" mode on a cheap zoom.


That's why your DOF is so shallow.

Because of the cheepo plastic? :-))


Funny you mention plastic!

Yes! I think so too!!

My shallowest DOF lens is my Schneider 25mm
f/0.95 which is all-metal and costs about $2500.00.

Someone took you for a ride:

https://www.bhphotovideo.com/c/produ..._21_012101_Xen
on_25_mm_f_0_95.html

The shallowest DOF I've
ever seen though was with a 65mm f/0.7 "Delft" X-Ray lens I once had. Old
projection TVs have 35mm f/0.5 lenses constructed using aspheric plastic
elements. They only had to transmitted one of three colours so achromatism
wasn't needed, their housings are some kind of glass-infused plastic. But to
prevent the plastic from deforming or melting (catching fire?) under the heat
of the bulb elements needed for projection, they had to use a silicone oil
liquid lens element.

I remember those tellys. The IQ was horrible! NTSC (Never Twice the Same
Colour) and those flimsy constructions put together...
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teleportation kills

On 11/6/2016 5:00 PM, RichA wrote:
On Sunday, 6 November 2016 16:09:44 UTC-5, peterN wrote:
On 11/6/2016 2:29 PM, RichA wrote:
On Sunday, 6 November 2016 13:36:21 UTC-5, peterN wrote:
On 11/6/2016 12:03 AM, RichA wrote:
http://www.pbase.com/andersonrm/imag...71533/original


Did you use a close up attachment?


--
PeterN

No, "macro" mode on a cheap zoom.


That's why your DOF is so shallow.

--
PeterN

Yes.


That's a normal characteristic of along lens, used for closeup. It has
nothing to do with a cheap lens. When I put an extension tube on my
Nikon 70-200, the DOF is quite shallow.

BTW, I was looking at some of your birds, and think they were nicely
exposed, and reasonably sharp. There was nice detail in the feathers.
Keep it up.


--
PeterN

On 07/11/2016 11:17, RichA wrote:
Pentax's 300mm f/4 is around $1000 but I'm reluctant to buy it because it appears not to be that great wide open, so what's the point?

This one?
http://www.photozone.de/pentax/643-pentax300f4
Tests pretty well at f4 from the look of that.
The difference in resolution stopped down one stop might be more evident
on a higher resolution body, but should be still pretty decent shot wide.